The present invention relates to a holding device for toroidal cores provided with windings.
Toroidal cores provided with windings such as, for example, toroidal core transformers, toroidal core chokes, or even simple potentiometers on occasion are not easy to secure in conjunction with other circuit elements. This is true on the one hand because they are relatively heavy and, on the other hand, they do not allow a direct, mechanical fastening since the toroidal core which is stable per se is completely surrounded by a winding, in many plies in certain applications, so that a mounting would have to engage at the winding. Accordingly, the toroidal core must be very rigidly secured and with an absolutely fixed location relative to other components since the winding ends must be connected to other stationary parts, and generally need to be soldered. Any relative motion between these parts would necessarily lead to damage.
It is known to fix toroidal cores in a special housing, to fix them either individually or together with other components such as for example further toroidal cores provided with windings, and to encapsulate the entire housing such that a unit consisting of a toroidal core and housing is created. The terminal lugs for the windings are then secured to the solder terminals, solder pins, etc. secured to the housing wall or secured to housing parts rigidly connected to the housing wall.
For the purpose of fastening toroidal cores provided with windings to circuit parts or the like where no housing can be provided, the toroidal core is generally clamped between two plates provided with an elastic layer on a side of the plates facing toward the toroidal core. The plates or a pin which is passed through the plates and simultaneously clamps the plates are secured to the corresponding device or to the circuit parts. This manner of fastening enables the toroidal core to be secured in stationary fashion to further circuit parts, for example to printed circuit boards or the like. In consideration of the existing weight of the toroidal core itself, however, the plates must be clamped relatively tightly against one another. This has a disadvantageous effect by way of a correspondingly high pressure on the winding of the toroidal core itself. Damage to the lacquer insulation of the individual windings occurs relatively easily. This is true because the mount is also exposed to relatively great temperature fluctuations.